A study published last week in the journal Stem Cell Reports has found new evidence for the use of stem cells for improving motor skills in mice. These findings provide potential new directions for future studies to explore the role of stem cells as a therapeutic approach in MS.
An animal model of MS was created using mice that have inflammatory damage to the insulating myelin surrounding nerve fibres in the brain and spinal cord. Stem cells grown in the laboratory were then transplanted into these mice, in order to identify whether stem cells were able to improve the disease course or severity, by affecting the immune systems of these mice.
Prior to the mice receiving any treatments, their disease was very advanced and many mice were paralysed and unable to walk. Following transplantation of the stem cells, 73% of the mice showed some clinical improvement in their disease symptoms and reductions in their motor disability. Many of the mice regained the ability to walk. These benefits were sustained for six months after transplantation.
The brains of these mice were then examined, to identify the causes of these improvements. The mice showed reductions in the amount of inflammation and demyelination of the nerve cells in the brain and spinal cord. When the levels of immune cells were measured, the mice showed an increased number of T regulatory immune cells, and reduced production of inflammatory molecules (cytokines). These changes are thought to underpin the observed clinical improvements in the mice.
Although these results suggest that the transplanted stem cells reduced levels of inflammation in mice with MS-like disease, the studies of stem cells in humans do not yet conclusively support the use of stem cells as a treatment for MS. Much more research is needed, both in animals and then in clinical trials of people with MS, to investigate the safety of stem cells and identify any benefits of this approach.